Signal-box



. v (No Model.) 2 Sheets-Sheet 1.

M. G. DAVIS.

SIGNAL BOX.

No. 451,689. Patented May 5, 1891.

UNITED STATES PATENT OFFICE.

MILTON G. DAVIS, OF WVEST SOMERVILLE, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO THE MUNICIPAL SIGNAL COMPANY, OF PORT- LAND, MAINE.

SIGNAL-BOX.

SPECIFICATION forming part of Letters Patent No. 451,689, dated May 5,1891.

Application filed June 18, 1890. Serial No. 355,824. (No model.

To all whom it may concern.-

Be it known that I, MILTON G. DAVIS, of West Sorherville, county of M'iddlesex, State of lllassachusetts, have invented an Improvement in Signal-Boxes, of which the following description, in connection with the accompanying drawings, is a specification, like letters and figures on the drawings representing like parts.

This invention has for its object to improve the construction of signal-boxes, such as is shown and described in United States Patent No. 375,083, dated December 20, 1887, granted to- M. Martin. As shown in said patent, a I 5 locking device is provided for the windingarm of the signal-transmitter,it consisting of a pivoted lever having upon it suitable pins or projections, which co-operate with a pin or pro ection on the winding-arm to lock said winding-armin'its abnormal position. I have fonndin practice that these pins are subjected to great wear, and after the boX has been in use some length of time they do not properly co-operate, and hence to provide suitable means by which proper adjustment may be given to said pins is one of the objects of this invention, and I have carried it out by arranging one or both pins eccentrically on a movable or rotatable block.

I have also found in practice that boxes are oftentimes deranged by the pull-down rods being tampered with,as by being pulled halt-way down and then being allowed to return to their normal position, which result 3 5 can be accomplished by the mechanism shown in the patent aforesaid. To-obviate this difficulty I have provided means for preventing the return movement of the pull-down rod unless given a complete movement, said 40 means being thrown out of engagement with the pull-down rod at a certain time, 01' when the winding-arm has been moved a proper distance to effect the transmission of the signal on its return movement, and held disengaged during the return movement of the said pull-down rod. Herein the pull-down rod, instead of directly engaging the crankarm that is attached to the winding-shaft of the transmitter, engages the winding-arm hav- 5 ing on it a block of insulating material proarm a is slotted at its outer end to receive a vided with a pin, said pin engaging the crankarm.

Figure 1 shows in front elevation a signalbox embodying tl'iisinventiomthe door of the box being removed; Fig. 2, a vertical section of the face-plate of the box, showing the operating parts; Fig. 3, a detail showing in full lines the crank-arm on the winding-shaft of the transmitter,and in dotted lines the winding-arm connected to it; Figs. at, 5, 6, and 7, details to be referred to.

The signal-box herein shown comprises a shell or case a, a face-plate a hinged to it, and a door (not shown) also hinged to it at the opposite side. The box contains a multiplesignal transmitter of any usual or suitable constructionsuch, for instance, as shown and described in patent to J. C. \Vilson, No., 320,032, dated June 17, 1S85said transmitter being contained in a box or case a attached to a supporting-plate arranged on a face-plate or in any other suitable manner. On the winding-shaft a of the multiple-signal transmitter a crank-arm a is secured. The crankpin a", attached to a block a of insulating material, secured to the windingarm b, pivoted at 2. The winding-arm b has on it apin 3, which co-operates with contact-springs 4 5, constituting a shunt for the multiple-signal transmitter. The winding-arm b is engaged by a pin 0 on the pull-down rod 0, and by said pin is moved into its abnormal position, as shown in Fig. at, to wind up the motor of the transmitter. The pull-down rod 0 is slotted, as at c, to form guide-passages for stationary guide-pins, and said pull-down rod has at its lower end a pull or finger piece 0 The pulldown rod 0 has formed on it at one side suitable teeth c which are engaged bya pawl 0 pivoted at c to the supporting-plate and held in engagement with said toothed portion by means of a spring o The pawl c has on it a pin 0 which lies in the path of movement of the winding-arm b, and when said windingarm is moved into its abnormal position, as shown in Fig. i, the said arm will engage the pin c and throw the pawl out of engagement with the ratchet toothed portion. The windin g-arm willbe held in its abnormal position by 100 means of thelocking'device, to be described, until the pull-down rodhasbeen returned to its normal position independently by means of a spring 10 and the winding-arm holding the pawl in disengaged position will allow said return movement of the pull-down rod. The pawl prevents return movement of the pulldown rod, except when it has been thrown out of engagement therewith by means of the winding-arm.

The locking device herein shown, which is alternately designed to engage and release the winding-arm and pull-down rod, is sub stantially the same as shown in the patent to Martin, aforesaid. It consists of a pivotal plate 0, (see Figs. 1, l, and 6,) having on it pins 6 e the latter adapted to co-operate with a pin b on the winding-arm and the former to be acted on by the inclined end portion a of the winding-arm I), and the pulldown rod has a shoulder c, which is engaged by the upper end of the said pivotal plate. A spring a is fastened to the plate 8, its outer or free end bearing against the frame-work, the purpose of which spring is to continually press the upper end of the plate 6 against the pulldown rod 0. Instead of the fixed pins 6 b as illustrated in the said patent, and which, as before stated, wear materially, I have arranged said pins so that they may be adjusted, and, as shown, said pins are located eccentrically on blocks or screws 1 5 b, which are adapted to be turned in their bearings and be held, preferably, in fixed position by means of clamping-screws 7 8, as best shown in Figs. 6 and 7. It is obvious that fora limited amount of adjustment but one pin need be eccentric.

lhe snpportingplate for the operatingparts and the removable dial having a plate of glass in it, as herein shown, form no part of my invention.

I claim- 1. In a signal-box, a signal-trans1nitter, a winding-arm, and a pull-down rod having teeth,combined with a pawl adapted to engage the said teeth and to be engaged by the Winding-arm when the latter is depressed to disengage it from the aforesaid teeth, substantially as described.

2. In a signal-box, a signal-transmitter, a winding-arm, a pull-down rod, and a looking device, and pins on the winding-arm and locking device, which co-operate to lock the winding-arm in its abnormal position, one of which pins is arranged eecentrically on a movable block or stud, substantially as described.

3. In a signal-box, a signal-transmitter and a crank-arm attached to the winding-shaft thereof, combined with a winding-arm, insulated block thereon, and a pin connecting the insulated block with the crank-arm, substantially as described.

4. In a signal-box, a sigrial-transmitter, a winding-arm having a pin or projection, and a pull-down rod to actuate it, combined with a locking device having an adjustably-held pin or projection to co-operate with the pin or projection on the winding-arm, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MILTON G. DAVIS.

Witnesses:

GEO. W. GREGORY, BERNICE J. NoYEs. 

